# year    value 
 1900    -1.16 
 1901     0.14 
 1902     0.43 
 1903     0.26 
 1904    -0.88 
 1905    -0.78 
 1906     0.06 
 1907    -0.78 
 1908    -0.16 
 1909    -0.74 
 1910     0.13 
 1911    -0.84 
 1912    -0.32 
 1913    -0.29 
 1914      1.4 
 1915     0.18 
 1916     0.49 
 1917     -1.3 
 1918    -0.86 
 1919    -0.25 
 1920    -0.49 
 1921     0.39 
 1922     -0.7 
 1923    -0.27 
 1924    -0.19 
 1925     0.28 
 1926     0.86 
 1927    -0.31 
 1928    -0.56 
 1929    -1.84 
 1930    -0.75 
 1931    -0.45 
 1932     0.64 
 1933    -0.66 
 1934    -0.41 
 1935     0.38 
 1936    -0.85 
 1937     0.11 
 1938     0.04 
 1939    -0.12 
 1940    -0.11 
 1941     0.29 
 1942    -0.76 
 1943    -0.25 
 1944     1.15 
 1945    -1.13 
 1946     0.16 
 1947    -1.05 
 1948     0.38 
 1949     0.49 
 1950    -0.76 
 1951    -0.59 
 1952     0.77 
 1953      0.3 
 1954    -0.59 
 1955     0.64 
 1956    -0.64 
 1957    -0.26 
 1958     1.27 
 1959      0.2 
 1960     0.69 
 1961     0.74 
 1962     0.54 
 1963    -0.01 
 1964    -0.27 
 1965    -0.25 
 1966     0.61 
 1967    -0.86 
 1968    -0.15 
 1969     -1.6 
 1970    -0.01 
 1971     -0.2 
 1972    -0.78 
 1973     0.17 
 1974    -0.02 
 1975     0.69 
 1976     0.38 
 1977    -0.78 
 1978    -0.27 
 1979    -0.44 
 1980     0.48 
 1981     1.08 
 1982     0.12 
 1983     1.62 
 1984     0.21 
 1985     -0.9 
 1986     0.35 
 1987     0.89 
 1988     0.67 
 1989     1.28 
 1990     1.33 
 1991     0.78 
 1992     1.33 
 1993     0.84 
 1994      0.1 
 1995     1.74 
 1996    -0.02 
 1997     1.12 
 1998     1.65 
 1999     1.98 
 2000     1.86 
 2001     0.78 
 2002     2.38 
 2003     0.31 
 2004     1.76 
 2005     0.73 
 2006     0.65 
 2007     2.52 
 2008     0.57 
 2009     0.88 
 2010      0.4 
 2011     0.45 
 2012      0.6 
 2013     0.82 
 2014     0.83 
 2015     1.72 
 2016     3.02 
 2017     1.92 
 2018     1.09